When Income Increases from $20,000 to $30,000 the Quantity of Inter-City

Multiple Choice

When income increases from $20,000 to $30,000 the quantity of inter-city bus trips taken per year decreases from 10 to 8.Hence

A) inter-city bus trips are a normal good.
B) the income elasticity of demand for inter-city bus trips is -1.8.
C) the income elasticity of demand for inter-city bus trips is -0.56.
D) Both answers A and B are correct.
E) Both answers A and C are correct.